Necessary vs. Need — What's the Difference?

Needed or required

A need is something that is necessary for an organism to live a healthy life. Needs are distinguished from wants.

Unavoidably determined by prior conditions or circumstances; inevitable

A condition or situation in which something must be supplied in order for a certain condition to be maintained or a desired state to be achieved

Logically inevitable

Something required or wanted; a requisite

Required by obligation, compulsion, or convention

Necessity; obligation

Something indispensable.

A condition of poverty or misfortune

Required, essential, whether logically inescapable or needed in order to achieve a desired result or avoid some penalty.

To be under the necessity of or the obligation to

Unavoidable, inevitable.

To have need of; require

(obsolete) Determined, involuntary: acting from compulsion rather than free will.

To have an obligation (to do something)

A place to do the "necessary" business of urination and defecation: an outhouse or lavatory.

To be subject (to an action) by obligation

(obsolete) Necessity.

To want to be subject to

Such as must be; impossible to be otherwise; not to be avoided; inevitable.

To be in need or want.

Impossible to be otherwise, or to be dispensed with, without preventing the attainment of a desired result; indispensable; requisite; essential.

To be necessary.

Acting from necessity or compulsion; involuntary; - opposed to free; as, whether man is a necessary or a free agent is a question much discussed.

A requirement for something; something needed.

A thing that is necessary or indispensable to some purpose; something that one can not do without; a requisite; an essential; - used chiefly in the plural; as, the necessaries of life.

Lack of means of subsistence; poverty; indigence; destitution.

A privy; a water-closet.

(transitive) To have an absolute requirement for.

Such things, in respect to infants, lunatics, and married women, as are requisite for support suitable to station.

(transitive) To want strongly; to feel that one must have something.

Anything indispensable;

(modal verb) To be obliged or required (to do something).

Absolutely essential

(intransitive) To be required; to be necessary.

Unavoidably determined by prior circumstances;

To be necessary (to someone).

A state that requires supply or relief; pressing occasion for something; necessity; urgent want.

Want of the means of subsistence; poverty; indigence; destitution.

That which is needful; anything necessary to be done; (pl.) necessary things; business.

Situation of need; peril; danger.

To be in want of; to have cause or occasion for; to lack; to require, as supply or relief.

To be wanted; to be necessary.

Of necessity. See Needs.

A condition requiring relief;

Anything that is necessary but lacking;

The psychological feature that arouses an organism to action toward a desired goal; the reason for the action; that which gives purpose and direction to behavior;

A state of extreme poverty or destitution;

Require as useful, just, or proper;

Have need of;

Have or feel a need for;